Vice President Biden hugs Madeleine Smith after he spoke about the release of the First Report of the White House Task Force to Protect Students from Sexual Assault, April 29, 2014 (AP Photo)

“We know the numbers: one in five of every one of those young women who is dropped off for that first day of school, before they finish school, will be assaulted, will be assaulted in her college years.”

–Vice President Biden, remarks on the release of a White House report on sexual assault, April 29, 2014

“It is estimated that 1 in 5 women on college campuses has been sexually assaulted during their time there — 1 in 5.”

NOTE: This article has been expanded and updated, with a new URL. Please read the updated version.

Reports of sexual assault on college campuses spurred the White House earlier this year to launch a task force to examine the issue. The group’s report was issued on Tuesday, and the first sentence of the report echoes what both the president and vice president have asserted in public: “One in five women is sexually assaulted in college.”

Where does this oft-repeated statistic come from? We dug into the data so you don’t have to.

The Facts

This statistic is derived from a 2007 study, The Campus Sexual Assault Study, which was conducted for the Justice Department’s National Institute of Justice. The researchers, led by Christopher Krebs of RTI International, also surveyed men, but the statistic cited by the administration focuses on women so we will look carefully at that part of the study.

In the Winter of 2006, researchers used a Web-based survey to interview undergraduates at two large public universities, one in the Midwest and one in the South. A total of 5,446 undergraduate women, between the ages of 18-25, participated as part of a random sample. The survey was anonymous and took about 15 minutes to complete. (Participants received a $10 Amazon.com certificate for participating.)

So, first of all, it’s important to remember that this is a single survey, based on the experiences of students at two universities. As the researchers acknowledged, these results clearly can be generalized to those two large four-year universities, but not necessarily elsewhere. Moreover, the response rate was relatively low:

“Another limitation of the CSA study, inherent with Web-based survey, is that the response rates were relatively low. Although the response rates were not lower than what most Web-based surveys achieve, they are lower than what we typically achieve using a different mode of data collection (e.g. face-to-face interviewing).”

The survey found that 1,073 women, or 19 percent, said that they experienced attempted or completed sexual assault since entering college. The actual breakdown was that 12.6 percent experienced attempted sexual assault and 13.7 percent experienced actual sexual assault. (There was some overlap.)

The sexual assault instances were further divided into sexual assault while incapacitated from drugs or alcohol or sexual assault through physical force. Most of the sexual assaults were identified as rapes, though the report said “sexual battery” could have included “sexual touching,” such as forced kissing or fondling.

Notice that the percentage of sexual assaults –13.7 percent—was lower than the one-in-five figure cited by administration officials. (It is more like one in seven.) That’s because the president and vice president used careful phrasing that covered a student’s entire time in college. The overall survey interviewed students that included freshmen, sophomores and juniors.

In a 2009 report, the researchers released a closer look at the data (embedded below). This report showed that out of the subset of seniors surveyed (1,402 women), that 19 percent (about 287) had experienced sexual assault.

“Women surveyed in their senior year of college (those having the longest risk period for sexual assault since entering college) had the greatest cumulative prevalence of each type of completed sexual assault,” the report said, referring to Table 1. “Almost 20% of the seniors experienced some type of sexual assault since entering college, with 6.9% experiencing physically forced sexual assault and 16.0% experiencing incapacitated sexual assault.”

In other words, information that is localized to the seniors at two colleges has now been extrapolated by politicians to the universe of college experience. (The report itself states that the data are limited just to those universities.) And to some extent, the results depend on how questions are phrased and answers interpreted. Below we have embedded the key questions that led to the statistic cited by the White House.

On its Web site, the National Institute of Justice notes that rapes and other forms of sexual assault are among the most underreported crimes, but that “researchers have been unable to determine the precise incidence of sexual assault on American campuses because the incidence found depends on how the questions are worded and the context of the survey.” It said that two parallel surveys of American college women were conducted in 1997 and came up with very different results, with one survey showing rapes were 11 times higher than the percentage in the other survey. The reason appears to be because of how the questions were worded. (Hat tip to Washington Post polling analyst Scott Clement for pointing us to this page.)

NIJ adds:

“Regardless of which studies are most accurate, the often-quoted statistic that one in four American college women will be raped during her college years is not supported by the scientific evidence. Nonetheless, several studies indicate that a substantial proportion of female students — between 18 and 20 percent — experience rape or some other form of sexual assault during their college years.”

Krebs made the following points in an email:

We approached this project objectively and implemented it with as much methodological rigor as possible. This gives us confidence in the results. I do think there is room for improvement in our methods and I think a larger sample of universities and respondents would yield results that are more representative, but in the face of some significant challenges we implemented a study using solid methods and we have tried to be very clear about what we did, how we did it, and what we learned.

The Pinocchio Test

We are not going to make a ruling at this time, pending additional information. As an interesting article from the University of Minnesota-Duluth newspaper makes clear, sexual violence is too rarely reported. So the White House should be applauded for calling attention to this issue.

But readers should be aware that this oft-cited statistic comes from a Web-based survey of two large universities, making it problematic to suggest that it is representative of the experience of all college women.

NOTE: This article has been expanded and updated, with a new URL and a Pinocchio rating. Please read the updated version.

Verdict Pending

Glenn Kessler has reported on domestic and foreign policy for more than three decades. He would like your help in keeping an eye on public figures. Send him statements to fact check by emailing him, tweeting at him, or sending him a message on Facebook.

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